1. Technical Field
The present disclosure relates to a stopping control device for a vehicle such as an automobile.
2. Description of the Related Art
As a travel control for a vehicle such as an automobile, there has hitherto been known an all vehicle speed ACC (adaptive cruise control) and the control is sometimes referred to “constant vehicle speed and inter-vehicle distance control for all vehicle speed range.” In general, the all vehicle speed ACC includes a constant vehicle speed control, an inter-vehicle distance control and a stopping control. The inter-vehicle distance control and the stopping control are executed when respective preset conditions are satisfied during the constant vehicle speed control is being executed.
In the constant vehicle speed control, braking force and driving force of a vehicle are as necessary controlled so that the magnitude of a difference between an actual vehicle speed and a preset reference vehicle speed becomes equal to or less than a reference value. In the inter-vehicle distance control, a determination is made as to whether or not there is a preceding vehicle and when it is determined that there is a preceding vehicle, braking force and driving force of a vehicle are as necessary controlled so that the distance between the own vehicle and the preceding vehicle becomes within a predetermined range including a preset reference distance. Further, in the stopping control, the own vehicle is stopped by increasing the braking force of the own vehicle when the preceding vehicle stops and the distance between the own vehicle and the preceding vehicle becomes equal to or less than the preset reference distance, and the own vehicle is maintained in a stopped state.
For example, in Japanese Patent Application Laid-open No. 2015-93629, there is described a stopping control device configured to increase, when the vehicle is stopped by the stopping control, braking forces of the vehicle so as to suppress moving of the vehicle during an engine that is stopped by idling stop control is re-started. The braking force of the entire vehicle is increased so that it becomes a predetermined value that is a sum of a braking force for maintaining the vehicle in a stopped state and a braking force for counteracting a driving force generated during the period of time of re-starting the engine. When the braking force of the entire vehicle is increased to be the predetermined value, the vehicle can be prevented from moving during the period of time of re-starting the engine.
In the stopping control device described in the above-mentioned Japanese Patent Application Laid-open publication, as the braking force of the entire vehicle is increased until an increase amount of the braking force by the stopping control becomes a predetermined value that is preset to prevent the vehicle from moving, allophone may be generated due to flowing of high pressure working liquid. For example, when the stopping control is executed during braking operation is conducted by a driver and, accordingly, the braking force of the entire vehicle is increased so that it becomes a sum of a braking force generated by braking operation of the driver and the predetermined value, the braking force of the entire vehicle may become a very high value, which causes distinguishable allophone to be generated. Especially, when a braking apparatus includes an electric pump and the working liquid is pressurized to high pressure by means of the electric pump being driven when increasing the braking force of the entire vehicle by the stopping control, operational noise is also generated due to driving of the pump. Consequently, when a braking apparatus includes an electric pump as described above, allophone that is generated when increasing the braking force by the stopping control is more distinguishable as compared to where a braking apparatus includes an accumulator.